Study looks at using sugars to treat inflammatory bowel disease

By Bernie Poitras

Keeping the gut microbiota, the micro-organisms living in our intestines, in balance is important in preventing disease.

A GlycoNet-funded project is looking at using glycans (sugars) to restore an imbalance that occurs in patients suffering from inflammatory bowel disease (IBD). The chronic digestive disease, which includes Crohn’s disease and ulcerative colitis, affects more than 200,000 Canadians.

“The gut microbiota is an ecosystem, much like a forest, and if there is any imbalance, the host or in this case, the person, suffers,” says Dr. Bastien Castagner, a GlycoNet Network Investigator and Assistant Professor at McGill University. “This imbalance can contribute to inflammation, obesity or in the case of our study, IBD.”

“Together with McGill University microbiologist Dr. Corinne Maurice, our team is researching the metabolism of the gut bacteria to understand what they eat,” he says. “Once we know that, we can suggest dietary glycans to change or modulate the gut microbiota to bring it back into balance in patients that suffer from IBD.”

Castagner says people who suffer from IBD are missing key bacteria from their gut. Glycans can offer a solution to help restore a healthy balance. His research looks to identify the right food to sustain and promote key bacteria in patient’s guts.

“Dietary glycans are a very important source of food for, and one of the main determinants of, the composition of gut microbiota,” he says. “The key goal is to alter the composition of the gut microbiota using these glycans to get it to a healthier state.”

Castagner says the idea of using glycans to alter the composition of the gut microbiota is not new. In fact, human milk includes oligosaccharides, sugars that help maintain a healthy composition of bacteria in breastfeeding infants.

To collect data and develop a proof of principle, Castagner works with a bioengineer who created a completely automated artificial gut. “The reactor mimics a large intestine and will help us validate our hypotheses on a complex community of micro-organisms,” he says.

GlycoNet’s one-year catalyst grant provided Castagner’s lab with the resources to hire a graduate student and a research associate to conduct the research.

“GlycoNet’s funding was crucial because we could gather data to create a proof of principle,” says Castagner.

Alongside his colleagues at McGill and other Network Investigators across Canada, Castagner is testing different glycans in the artificial gut to determine which ones bring the gut microbiota back to a healthy balance.

“We are also able to collaborate with other GlycoNet Investigators, and meet other experts in their respective fields of discipline, which is really helpful,” he says.

This strategy would also be applicable to other diseases, but before that can happen, Castagner says the strategy has to be tested in clinical trials on patients.